Yeah, the charts have never worked for me. I have enormous quads and am probably 5-10lbs heavier than the average competitive distance runner at my height, but I'm very lean. I don't think weight is the reason why.
I'm no scientist, but I figure genetically gifted runners typically possess a combination of efficient heart and lung function, high red blood cell production, abundant hemoglobin in red blood cells, long legs, mental resilience, strong recovery abilities, optimal muscle fiber ratios, etc.
I think a lot of those things for me are mediocre to above average but I think I do have top-tier lactic tolerance and clearance abilities.